160clc problems. Hydraulic stall.

[Diesel Dave]

See the speed sense solenoid (Y5) valve operation from the manual in screenshot below.
Suggest to monitor the speed sense solenoid signal to the two pump regulators by tee in a guage at the speed solenoid outlet port hose.

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[imgonnadigtochynaa]

Okay. And what should I see in this test? Pilot pressure decreasing as engine rpm pulls down?

 

[Diesel Dave]

Okay. And what should I see in this test? Pilot pressure decreasing as engine rpm pulls down?

As a load on the engine increases, the speed difference between target and actual engine speed becomes less.
The pump and valve controller decreases the voltage to the speed sensing solenoid valve which increases the speed sensing pilot oil pressure to the load piston.